<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
               "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
<head>
    <style type="text/css">
   body {
  background-color: #010101;
}
a{
    position: relative;
    display: inline-block;
    padding: 25px 30px;
    margin: 40px 0;
    color: #03e9f4;
    text-decoration: none;
    text-transform: uppercase;
    transition: 0.5s;
    letter-spacing: 4px;
    overflow: hidden;
    margin-left: 50px;
   
}
a span{
    position: absolute;
    display: block;
}
a span:nth-child(1){
    top: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg,transparent,#03e9f4);
    animation: animate1 1s linear infinite;
}
@keyframes animate1{
    0%{
        left: -100%;
    }
    50%,100%{
        left: 100%;
    }
}
a span:nth-child(2){
    top: -100%;
    right: 0;
    width: 2px;
    height: 100%;
    background: linear-gradient(180deg,transparent,#03e9f4);
    animation: animate2 1s linear infinite;
}
@keyframes animate2{
    0%{
        top: -100%;
    }
    50%,100%{
        top: 100%;
    }
}
a span:nth-child(3){
    bottom: 0;
    right: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(270deg,transparent,#03e9f4);
    animation: animate3 1s linear infinite;
}
@keyframes animate3{
    0%{
        right: -100%;
    }
    50%,100%{
        right: 100%;
    }
}
a span:nth-child(4){
    bottom: -100%;
    left: 0;
    width: 2px;
    height: 100%;
    background: linear-gradient(360deg,transparent,#03e9f4);
    animation: animate4 1s linear infinite;
}
@keyframes animate4{
    0%{
        bottom: -100%;
    }
    50%,100%{
        bottom: 100%;
    }
}
    </style>
</head>
<body>
     
    <a href="#streamer">
        Streamer button
      </a>
</body>
</html>

 